Question

If the length and breath of a rectangle are in the ratio $5:3$ and its perimeter is $144\mathrm{m}$ , find the area of the rectangle .

Answer 1

Given , the length of the breadth of the rectangle is $5:3$

and The perimeter of the rectangle is $144\mathrm{m}$

We can $5:3$ take as $5x:3x$

It is a known perimeter of rectangle is

$$\begin{gathered} 2\left(\mathrm{l}+\mathrm{b}\right)=144 \\ 2\left(5x+3x\right)=144 \\ 8x=72 \\ x=\frac{72}{8} \\ x=9 \end{gathered}$$

So, length and breath of rectangle is $45\mathrm{cm}$and $27\mathrm{cm}$

Area of rectangle :-

Area of rectangle $=$length $\times$breath

$$\begin{gathered} =45\times 27 \\ =1215{\mathrm{m}}^2 \end{gathered}$$

Hence, the required area of rectangle is $1215{\mathrm{m}}^2$ .